1. Technical Field
The present invention relates in general to an improved data processing system having a display and a pointing device, such as a mouse or a track ball, and in particular to a data processing system in which a pointing device indicates an object displayed on a display and performs a predetermined operation on the object.
2. Description of the Related Art
In known data processing systems having a graphic user interface (GUI), it is common to perform a predetermined operation on an object displayed on a display, where such an object may include an icon, a graph, a window frame, or a character. Such predetermined operations may include an actuation of a program associated with an icon, an expansion of a window, or moving a window. These predetermined operations may be accomplished by positioning a mouse cursor and clicking or double clicking a mouse button, or clicking and dragging the displayed object.
Along with the complication of GUI application programs, operations that may be performed on an object on a display have become diversified. To cope with the diversification of such operations, attempts have been made in the prior art to improve the user interface, and to improve the efficiency of the various operations.
PUPA 59-163666 discloses a graphic generator using multiple cursors that forms a cursor area in an area surrounding part of a graphic pattern, moves in a voluntary direction a graphic surrounded by the cursor area, and further adds or contracts the graphic along with the movement of the graphic.
PUPA 62-11927 discloses a calculator using an icon for display and selection of functions, where the functions possessed by each icon, the icon's position on the screen, the icon's shape, and menu data displayed when the icon is displayed are stored and controlled to display the content of menu data when an icon for controlling the cursor display is selected.
PUPA 62-259129 discloses an indication means for indicating voluntary two pointing spots with a relative distance therebetween on a tablet, and cursor control means for moving a graphic cursor displayed on a display following the movement of the graphic cursor between the two pointing spots, as well as changing the size of the graphic cursor in response to pressing a predetermined button.
PUPA 2-166506 discloses an information input apparatus that displays a cursor on a display screen in response to the operation of a pointing device, the cursor serving as a shape for representing the function of an operation means.
PUPA 4-34663 discloses a function for representing the scope of an object to be selected with a cursor for selecting and editing an object on a display, as well as allowing variation of the shape and size of the cursor for representing the scope of an object to be selected.
While the prior art discloses changing the shape and size of a mouse cursor in accordance with a different operation, the cursor serves only to select one object. Consequently, when an attempt is made to perform one of a plurality of possible operations, for example, the following processing steps will be followed:
(a) A specific object is selected by positioning a mouse cursor on the specific object and clicking a mouse button. At this time, the specific object changes color, inverts its display, and becomes shaded to indicate that it has been selected. However, the operation that is to be performed has not yet been established, and therefore, the operation is not performed on the object at this stage. PA0 (b) Then the menu on the upper part of the window is clicked to display a pull-down menu. PA0 (c) A desired operation menu is clicked from among a plurality of operation menus displayed in the pull-down menu. As a consequence, the desired operation is performed on the selected object.
Such an operation, however, requires many operation steps using a mouse cursor. The operation is thus inefficient. There is also known a method of performing a specific operation with a combination of a control key and the right button of the mouse as a short cut key to cope with the above operation. Users are obliged to memorize a specific key stroke. Such a method is also lacking in flexibility in the user interface.